(a-1/2b)[(a+1/2b)^2-(a-1/2b)^2](a^2+1/2ab+b^2)-2b(a^4-1),其中a=2,b=-1
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(a-1/2b)[(a+1/2b)^2-(a-1/2b)^2](a^2+1/2ab+b^2)-2b(a^4-1),其中a=2,b=-1
(a-1/2b)[(a+1/2b)^2-(a-1/2b)^2](a^2+1/2ab+b^2)-2b(a^4-1),其中a=2,b=-1
(a-1/2b)[(a+1/2b)^2-(a-1/2b)^2](a^2+1/2ab+b^2)-2b(a^4-1),其中a=2,b=-1
先化简,再求值.用到的公式主要是a²-b²=(a+b)*(a-b),主要运算是分配律.
原式=(a-1/2*b)*【(2a)*(b)】*(a²+1/2*b+b²)-2*a^4*b+2*b
=(2*a²*b-a*b²)*(a²+1/2*b+b²)-2*a^4*b+2*b
(分配,去掉括号,进行化简)
=3/2*a²*b^3-a*b^4+2*b
代入数据,得最终结果:-10.